With the development of mobile communications technologies, increasingly high demands are imposed on improvements of communication system capacity, optimization of pattern performance, and the like. FIG. 1 is a schematic structural diagram of an existing antenna array, where the antenna array is comprised of five antenna sub-arrays in a vertical direction. Generally, the horizontal spacing between radiating elements in the antenna sub-array is approximately less than half of an operating wavelength, and under certain power distribution, a requirement of the antenna array for low side lobes in horizontal beams can be met.
However, in an implementation scenario where an operating frequency band of the antenna array is a wideband, the horizontal spacing between the radiating elements in the antenna sub-array cannot meet the half-wavelength requirement for each frequency point in the wideband. As a result, the energy of the horizontal side lobes in the antenna array pattern is high, and ultra-wideband performance is poor. This affects the communication system capacity.